2-p-(nitrobenzamido)acetohydroxamic for treating urinary tract infections

ABSTRACT

1. A COMPOSITION FOR TREATING URINARY TRACT INFECTION CAUSED BY RREA SPLITTING PROTEUS ORGANISMS CONSISTING OF THE COMBINATION OF 2-(PNITROBENZAMIDO) ACETOHYDROXAMIC ACID AND A MEMBER SELECTED FROM THE GROUP CONSISTING OF AMPICILLIN, SULFAMETHOXAZOLE AND NITROFURANTOIN IN EFFECTIVE DOSAGE AMOUNT IN WHICH THE PROPORTION OF SAID HYDROXAMIC ACID TO AMIPICILLIN AND SULFAMETHOXAZOLE IS 2:1 AND TO NITROFURANTION 10:1.

United States Patent US. Cl. 424-229 1 Claim ABSTRACT OF THE DISCLOSURE Novel benzamidoacetohydroxamic acids of the formula:

R-Q-G oNHcmc ONHOH wherein R is nitro or chloro are potent inhibitors of urease. Combined with urinary tract antibacterials an improvement in the prevention of formation of urinary calculi in the presence of urea splitting organisms is observed This is a division of application Serial No. 280,563, filed Aug. 14, 1972, which, in turn is a division of application Ser. No. 144,322 filed May 17, 1971, now US. Pat. No. 3,728,380.

This invention is concerned with chemical compounds. More particularly it is concerned with compounds of the formula:

RQ-QONHCHwONHQH (I) wherein R is nitro or chloro and their combination with urinary tract antibacterial agents.

The compounds of formula I are potent urease inhibitors. They may be readily prepared according to this scheme:

R-Q-oONHCmcOOmH, Hmon R-Q-GONHCIEBCONHOH 0.11.011

wherein R is nitro or chloro. Exemplary of this scheme are the following:

EXAMPLE 1 2- (p-Nitr-obenzamido) acetohydroxamic Acid A solution of hydroxylamine hydrochloride (28 g. 0.4 mole) in methanol (145 ml.) was treated with a solution of KOH (37 g. 0.7 mole) in methanol (84 ml.). The resulting inorganic salt was removed and the filtrate treated with ethyl p-nitrohippurate (84 g. 0.3 mole). After stirring for 3 hours, a solid precipitated. The entire reaction mass was stirred in approximately 500 ml. of water. A white crystalline solid was separated by filtration and dried at 60 to 35 g. The filtrate was acidified with glacial acetic acid to pH 6, precipitating a white crystalline solid which was dried at 60 to 38 g. The two crops were combined with 15 g. from a similar run and recrystallized methanol to give 69 g. (67%), mp. 160-1".

Calcd. for C H N 0 C, 45.19; H, 3.79; N, 17.57.

Found: C, 45.10; H, 3.80; N, 17.53.

EXAMPLE 2 2- (p-Chlorobenzamido acetohydroxamic Acid Into a suspension of 209 g. (1.50 moles) of glycine ethyl ester hydrochloride in 1200 ml. of dry benzene was slowly added 263 g. (1.50 moles) of p-chlorobenzoyl chloride. This mixture was heated under reflux for 22 hours, then filtered and the white precipitate was recrystallized from methanol giving 292 g. (82.5%) of ethyl 2- (p-chlorobenzamido acetate, m.p. 114-117 C.

Anal. Calcd. for c,,H,,No,c1 (241.67): C, 54.67; H,

5.01; N, 5.80 Found: C, 54.95; H, 4.97; N, 6.08.

To a stirred solution of 58 g. (0.83 mole) of hydroxylamine hydrochloride in 350 ml. of anhydrous methanol was added a solution of g. of potassium hydroxide in ml. of anhydrous methanol. A white salt immediately precipitated. This mixture was cooled in an ice bath and the salt was removed by filtration. The filtrate was' placed into a 2 l. flask equipped with a stirrer, a thermometer and a drying tube. To the filtrate was added with stirring 100 g. (0.42 mole) of ethyl Z-(p-chlorobenzamido)acetate which went into solution. Approximately 2 minutes later a thick white precipitate formed. The mixure was stirred at room temperature overnight. The potassium salt was collected by filtration and dried at 60 to 90 g.

A second run of the same size was made with 91 g. of the potassium salt being obtained. The two crops of salt were combined making a total of 181 g. which was" placed in 2000 ml. of cold water. Glacial acetic acid (40 ml.) was added to give a final pH of 5. The white precipitate was collected by filtration and dried to g. in a 60 oven. The 160 g. of crude product was recrystallized from 4800 ml. of methanol. After cooling the solution overnight in the refrigerator, the product precipitated as white crystals which were collected by filtration and dried at 60 C. to 121 g. (63.8% overall yield), m.p. 171-172 C.

The anti-urease activity of the compounds of this invention is exemplified below:

TABLE I The inhibition oi ureese purified from Proteus mirabilis (Pr-91) and oi grease contained within intact cells of several species and strains of IO ens Concentration of inhibitor (or 50% inhibition of urease The compounds of this invention are valuable adjuncts in the therapy of urinary tract infection caused by urea splitting bacteria such as Proteus mirabilis whereby urea is decomposed to ammonia with resultant formation of insoluble salts such as ammonium magnesium phosphate giving rise to calculi formation and obstruction posing a.

0 site of reinfection impairing the efficacy of otherwise effective urinary tract antibacterials such as ampicillin, sulfamethoxazole and nitrofurantoin.

When the compounds of this invention are administered in conjunction with known antibacterial agents to rats in which a Proteus mirabilis genitourinary tract infection has been induced, the appearance of calculi is diminished and sometimes prevented. Also, at times, dissolution of formed calculi is accomplished through this joint therapy.

The following table is illustrative of the beneficial result achieved through the concomitant therapy referred to above:

TAB LE II Calculi in rats after 7 days infection with Proteus mirabilis (Pr91) [Compounds or combinations of compounds were administered t.i.d. at the indicated dosages for 6 days beginning 24 hours after infection] Statistical significance of Mean mg. the difference phosbetween an Test for Rats phorus as experimental potentiation 1 Dosage. per calculi per and the con- Compound(s) mg./kg group bladder trol group 1 E U AB None None 50 5. 4 Suliamethoxazole 12.5 10 1. 9 01 Ampicillin 12. 5 9 1. 1 05 Nitrolurantoin 2. 5 9 2. 2 02 1 Com ound of Example 1. 25 10 3. 3 02 50 9 1. 0 01 Com ound of Example 2- 25 8 3. 3 05 0 50 7 2. 3 02 Compound of Example 1- 50 Plus 9 0. 3 01 01 01 Sulfamethoxazole 2. 5 Compound of Example 1. 25

D 118 0. 6 01 01 01 Suliamethoxazole 12. 5 Compound of Example 2 50 plus 9 0. 9 01 01 01 Suli'amethoxazole 12. 5 Compound of Example 2- 25 D1115 9 0.9 01 01 01 Sultamethoxazole 12. 5 Compound of Example 1. 50

plus 10 0. 3 01 01 01 Nitrofurantoin 2. 5 Compound of Example 1. 25

plus 10 1. 2 01 10 10 Nitroiurantoin 2. 5 Compound ot Example 2. 50

plus 9 0. 1 01 01 01 Nitroiurantoln 2. 5 Compound of Example 2- 25 plus 10 0. 8 01 01 01 Nitroturantoin 2. 5 Compound of Example 1- 50 p us 10 0. 1 01 01 01 Ampicillln 12. 5 Compound of Example 1. 25

plus 0. 2 10 10 10 Ampicillin 12. 5 Compound of Example 2. 50

plus 9 0. 1 01 01 01 Ampicillin 12. 5 Compound 0! Example 2.

plus 10 0. 1 l0 01 01 Ampicillin 12.5

1 Statistical evaluation was by the Wilcoxon rank sum test [Wilcoxon et al. "Some Rapid Approximate Statistical Procedures," Lederle Laboratories, 7-9 (1964)].

1 The number is the probability that the difierence in the mean mg. phosphorus as cystic calcuh between rats receiving an antibacten'al agent (AB) only or an ureas inhibitor (EU) onl both (AB) and (E U) on the other, is a chance occurrence.

on the one hand. and the mean mg. phosphorus as cystic calculi from rats receiving References Cited UNITED STATES PATENTS JEROME D. GOLDBERG, Primary Examiner US. Cl. X.R. 

1. A COMPOSITION FOR TREATING URINARY TRACT INFECTION CAUSED BY RREA SPLITTING PROTEUS ORGANISMS CONSISTING OF THE COMBINATION OF 2-(PNITROBENZAMIDO) ACETOHYDROXAMIC ACID AND A MEMBER SELECTED FROM THE GROUP CONSISTING OF AMPICILLIN, SULFAMETHOXAZOLE AND NITROFURANTOIN IN EFFECTIVE DOSAGE AMOUNT IN WHICH THE PROPORTION OF SAID HYDROXAMIC ACID TO AMIPICILLIN AND SULFAMETHOXAZOLE IS 2:1 AND TO NITROFURANTION 10:1. 